000 AXNT20 KNHC 061136 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST SUN JAN 06 2008 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND THE ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS... WEATHER OBSERVATIONS...AND RADAR. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 8N13W 2N25W 2N38W EQUATOR AT 47W INTO NE BRAZIL. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 80-100 NM EITHER SIDE OF THE AXIS EAST OF 35W. SIMILAR CONVECTION IS FOUND FROM THE EQUATOR TO THE COAST OF AFRICA EAST OF 7W. ...DISCUSSION... GULF OF MEXICO... RIDGING ANCHORED ON A DEPARTING 1033 MB HIGH CENTERED JUST NE OF BERMUDA DOMINATES THE FLORIDA PENINSULA AND THE ENTIRE GULF OF MEXICO. THIS FEATURE IS PRODUCING 15 TO LOCALLY 20 KT ELY TO SELY SURFACE FLOW OVER THE REGION. FRAGMENTS OF BROKEN TO OVERCAST STRATOCUMULUS CLOUDS WITH EMBEDDED LIGHT RAIN REMAIN OVER MOST OF THE GULF OF MEXICO...BUT PARTICULARLY OVER THE BAY OF CAMPECHE AND THE N-CENTRAL GULF WATERS. THE ELY WINDS ARE BRINGING IN PATCHES OF LOW LEVEL CLOUDS THROUGH THE STRAITS OF FLORIDA. IN THE UPPER LEVELS...RIDGE AXIS HAS SHIFTED EASTWARD AND NOW EXTENDS OVER THE W ATLC ALONG 75W. NEARLY ZONAL FLOW DOMINATES THE GULF WITH MODERATE SUBSIDENCE. A WEAK UPPER LEVEL TROUGH IS ON THE HEELS OF THE RIDGE AND EXTENDS OVER THE SE U.S. WITH STRONG SUBSIDENCE IN ITS WAKE. THE SURFACE RETURN FLOW IS FORECAST TO REMAIN IN PLACE OVER THE ENTIRE GULF OVER THE NEXT 24 TO 36 HOURS WITH INCREASING CHANCES FOR SHOWER ACTIVITY OVER THE NW GULF. A WEAK COLD FRONT IS FORECAST TO MOVE OFF THE TEXAS COAST ON TUE. CARIBBEAN SEA... THE REMNANTS OF A WEAKENING FRONTAL BOUNDARY IS PRODUCING SCATTERED TO NUMEROUS SHOWERS AND ISOLATED TSTMS ACROSS THE NORTHERN LEEWARD ISLANDS...THE UK/US VIRGIN ISLANDS...PUERTO RICO AND DOMINICAN REPUBLIC. THIS SHOWER ACTIVITY LEFT 1.64 INCHES OF RAIN IN SAN JUAN SATURDAY EVENING. MODERATE TO LOCALLY STRONG TRADEWINDS ARE OVER THE ENTIRE CARIBBEAN SEA WITH PATCHES OF BROKEN LOW CLOUDS AND SCATTERED SHOWERS ESPECIALLY OVER THE GULF OF HONDURAS AND BETWEEN THE SAN ANDRES ISLAND AND THE CARIBBEAN COAST OF NICARAGUA. PATCHES OF LOW LEVEL CLOUDS WITH LIGHT RAIN/DRIZZLE ARE SEEN OVER W PANAMA AND COSTA RICA. ALL THIS ACTIVITY IS ASSOCIATED WITH LOW LEVEL CONVERGENCE. AN ASCAT FROM AROUND 0300 UTC SHOWED NE TO E WINDS OF 20 TO 25 KT ACROSS THE WESTERN CARIBBEAN. IN THE UPPER LEVELS...BROAD MID TO UPPER LEVEL SOUTHWESTERLY FLOW COVERS THE ENTIRE CARIBBEAN SEA WITH STRONG SUBSIDENCE NOTED OVER THE FAR NW CARIBBEAN NORTH OF 19N AND EXTENDING EASTWARD OVER CUBA...JAMAICA AND HISPANIOLA. NO MAJOR CHANGES ARE EXPECTED ON THE WEATHER PATTERN DURING THE NEXT 24 TO 36 HOURS. ATLANTIC OCEAN... A 1033 MB HIGH IS OVER THE WESTERN ATLANTIC JUST NE OF BERMUDAS COVERING THE ENTIRE WEST ATLC AND PARTS OF THE CENTRAL ATLC. A DECAYING STATIONARY FRONT ENTERS THE AREA NEAR 31N41W THEN CONTINUES SW ACROSS THE CENTRAL ATLANTIC TO JUST N OF THE NORTHERN LEEWARD ISLANDS. A VAST AREA OF BROKEN COLD AIR STRATOCUMULUS CLOUDS ARE NOTED NW OF THE FRONT WITH NE SURFACE WINDS OF 15-25 KT. A SURFACE TROUGH IS ALSO OVER THE CENTRAL ATLANTIC FROM 29N38W TO 19N40W. A WEAK SURFACE LOW IS ALONG THE TROUGH AXIS 23N40W. A SWIRL OF LOW CLOUDS DEFINES THE CENTER OF THE LOW ON SATELLITE PHOTOS. THERE ARE SCATTERED SHOWERS ON THE NORTHERN END OF THE TROUGH. A 1030 MB HIGH IS OVER THE EAST ATLANTIC NORTH OF THE MADEIRA ISLANDS NEAR 35N17W MOVING EWD. IN THE UPPER LEVELS...RIDGE COVERS THE BAHAMAS AND THE WEST ATLANTIC W OF 70W. A SHORT WAVE TROUGH IS ALONG 62W/63W WITH THE BASE OF THE TROUGH JUST N OF THE VIRGIN ISLANDS. AN AREA OF MOISTURE WITH EMBEDDED SHOWERS IS AHEAD OF THE TROUGH AXIS COVERING THE AREA BETWEEN 53W-61W N OF 20N. THIS ACTIVITY IS ALSO BEHIND THE AFOREMENTIONED WEAKENING FRONTAL SYSTEM. FURTHER EAST...A RIDGE IS OVER THE CENTRAL ATLANTIC N OF 20N BETWEEN 42W-62W. AN ELONGATED UPPER LEVEL LOW IS CENTERED OVER THE EAST ATLANTIC ALONG 32W/33W N OF 17N. A PLUME OF BROKEN JET CIRRUS CLOUDS IS E OF THE UPPER TROUGH FROM THE CAPE VERDE ISLANDS ALL THE WAY NORTH TO THE AZORES. THE FLOW IN THIS REGION IS VERY DIFLUENT WITH SOME OF THE ENERGY MOVING AROUND THE PERIPHERY OF AN AMPLIFIED UPPER LEVEL ANTICYCLONE OVER THE FAR EASTERN ATLANTIC SITUATED JUST SOUTH OF THE CANARY ISLANDS. $$ GR